1. Field of the Invention
The present invention relates to digital broadcast radio systems, and, in particular, to the provision of local information to a user in a digital broadcast radio system.
2. Description of the Related Art
In recent years, satellite-based digital radio has grown in popularity among both urban and rural listeners. FIG. 1 depicts a conventional digital satellite broadcast radio system 100. System 100 typically includes not only one or more satellite transmitters 106 and receivers 104, 108 but also terrestrial transmitters 102, 110, which complement the satellite signals in areas where they may be blocked. For example, terrestrial transmitters 102, 110 may be deployed in major metropolitan areas to fill the gaps created by blockage of satellite signals by tall buildings.
FIG. 2 illustrates the manner in which conventional digital satellite broadcast radio system 100 transmits local information, such as local news, traffic, and weather, to a user via N metropolitan channels. For regulatory compliance, each of terrestrial transmitters 102, 110 broadcasts each of the N metropolitan channels to every receiver 104, 108 in the system, regardless of where the receiver is located. As such, a user in a particular region must find and tune his receiver to the particular channel that carries the local traffic information for his region. For example, a satellite radio user located in New York City receives not only the New York City traffic channel but also numerous other channels containing traffic information for other metropolitan areas, and the user must find the specific metropolitan channel that carries the New York City traffic information. Locating and tuning to one specific metropolitan channel from among the many other metropolitan channels is cumbersome and time-consuming.